Additional Details courtesy of WOTC for Modern: With the exception of basic land cards, a player’s combined deck and sideboard may not contain more than four of any individual card, counted by its English card title equivalent.All cards named Plains, Island, Swamp, Mountain, and Forest are basic. (The five Ice Age block snow-covered lands -- Snow-Covered Plains, Snow-Covered Island, Snow-Covered Swamp, Snow-Covered Mountain, and Snow-Covered Forest -- are also basic lands. Note that snow-covered lands are permitted only in formats that allow expansions from the Ice Age block to be used.)​​Please visit http://magic.wizards.com/en/gameinfo/gameplay/formats/modern for most recent sets and banlist.